Carbureter



E. PI LAMB. CARBURETEH' APPLICATION FILED JUNE 7,1918.

Patented Apr. 26, 1921.

4447/1 IIIIILIIII| IIII I" [Illa glufuenlnr UNITED STATES APATENT carica.

ELDEN P. LAMB, 0F CAMDEN, MAINE, ASSIGNOR OF ELEVEIITWENTIETHS T0 JOHN BIRD, OF CAMDEN, MAINE.

GARBURE'TER.

Specification of Letters Patent.

' Patented Apr. 26, 1921.

Application led June `7, 191,8. Serial No. @38;690.

useful Improvements in Carbureters; and I do hereb)v declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the Same.

This invention relates to carbureters del signed for use with internal combustion en- The general object of the invention is to use a light or highly volatile liquid fuel for starting and subsequent-ly discontinue the use of the light fuel and substitute a heavy fuel for continuingthe operation ofthe en lVith this and other more specific objects in view the invention comprises certain novel constructions, combinations and arrangements of parts, as will be hereinafter mo-re fully described and claimed.

The drawing 'shows aA vertical sectional view through the carbureter.

This improved carbureter comprises, as an entirety, a casing having a mixing chamber, two fuel reservoirs, one for light and one for heavy fuel, a passage for air to be carbureted, said passage conducting the air laterally into the upper portion of the casing and through an air inlet in the lower part of the sage; a middle part containing the fuel,

mixing chamber, a choke valve "forl the air'A passage and-a means controlled by the choke valve for admitting the light fuel to the mixing chamberabove the air inlet or. for cutting off the supply of light fuel from said mixing chamber according to the extent to which the choke valve is opened; also a means for atomizing or delivering the heavy fuel in a multiplicity of jets, or ine spray, within the air current entering the mixing chamber, and a heat interchanging apparatus for heating said heavy fuel prior .to its enteringinto the spraying or atomizing means. f

In the preferred embodiment illustrated, the casing of the carbureter comprises three principal parts: (1;) An upper part inclosingthe mixing chamber and air inlet pasreservoirs; allower part comprising a chamber for receiving hot gas, preferably heavy fuel.

gases of combustionA from the engine exhaust.` The three principal parts referred to are clamped together` by a central tubular body passing completely through the member containing the hot gas or heat interchanging chamber and the fuel reservoirscontaining member,.said tubular body being threaded into the'part containing the mixing chamber, and carrying athreaded nut on its lower end by which thesaid three principal parts may be clamped together. The middle part of thecasing comprises a ,reservoir 1, intended to contain fuel oil of the heavier type, and incloses a float 2, controlling a lever 3, which actuates a needle valve 4 adapted to regulate the iow of the fuel oil throughthe inlet 5, from a source of supply into the reservoir 1. lVithin the upper part or member of the casing is a mixin chamber 2lia from which an outlet 28 for carbureted air leads to the manifold of the engine,'and within the outlet 28 is the usual throttle valve 27.

The fuelreservoir l is formed in a separate .casting having a central opening and a frusto-conical bottom la. Within a central opening in the member containing the reservoir 1 is a tubular body 50, having threaded flanges 51 by which said tubular l body is secured to the upper member of the casing, equall spaced lateral openings 52 between said anges, and longitudinal stiffening ribs 53. The lower portion of the tubular body 50 extends below the bottom of the reservoir/1 and is chambered as indi'cated at 12- and 15 constituting a fuel chamber exterior of the reservoir 1, adapted to be heated by hot gases. Below the frustoconical'bottom la of the reservoir 1, parallel therewith, and lying closely adjacent thereto, is a thin wall 8, formed, preferably, of

metal of high heat conductivity and spaced from the frusto-conical bottom 1a so as to confine a thin film of fuel entering from said reservoir1 l, through an opening 6, the spaceA between the wall 8' andthe frusto-conical bottom la, constituting a film chamber 7 for From the film chamber 7 ducts 11 lead through the wall of the extension on the tubular member 50 into the said chamber l2. l l

Surrounding the lowerl portion or extension of the tubular member 50 containing the chambers12, 15, is a chamber 9a,".for heated air or gases, that may be received through the conduit 9, which is controlled b the butterfly valve/10.A The shell of the cliambei` 9a may be secured in place, as previously stated, by a nut .50a threadedonto the lower end of the tubular member 50. Slidably guided within the bore of the tubular member 50 is a' hollow stem 16 having at its lower end within the chamber 12, 15, a piston 14 provided with orifices 13, and at its upper end an atomizing valve 22 haw' ing a conical surface or seatJ 22n adapted to fit upon a corresponding conical seat 24 on the .upper end of said tubular member 50. Opening just above the conical surface 22a in the said valve 22 is a series of radial ducts 23 which communicate with the upper end of the bore in the hollow stem 16, the' lower end of said bore in the hollow stem 16 opening into the space 15 above the piston 14 by means of lateral orifices 26. A spring 21 surrounding the stem 16 bears upon piston 14 and tends to forc the piston 14, stem 16 and valve 22 downward, normally causing the valve to seat. In operation, hammering of the valve is prevented by the perforated piston 14, acting inconjunction'with the chamber 12, 15, as a dash pot.

Threaded into the vbottom of the tubular member 50 is a large plug 12a, and threaded centrally in said plug 12a is an' adjusting member 19 having a knurled head 20. The adjusting member 19 is bored and counterbored. A needle valve or metering valve 18 is seated ,in the bore of member 19 and prjects upward into the 4stem 16, fthe' stem of said needle valve fitting snuglythe bore in the lower end of the hollow. stem 16. The Aupper end of said valve constitutes along tapering portion that coperates with the constriction 17 in the said stem. The lower end of the needle valve rests upon' a plug 19- within thecounterbore of the member 19, said plug being supported'by a screw 20. I

Fuel admitted from the reservoir 1 through the orifice 6 finto the chamber 7 f,

spreads out in a thin filnf, and when the engine is running-is constantly in contact with the hot metallic la'yer 8 heated-by exhaustv gases filling the heating chamber 9% Thus heat is interchanged between the hot gases in the chamber 9* and the thin film of fuel in the chamber 7. The fuel so heated finds its way/through the ducts 11 into the space'v 12 beneath the piston 14 and is drawn up through the orifice 13 in the pistqn 14' into the space 15 and thence into the interiorofv the stern 16, through the lateral orifices 26, past the` constriction 17 around the taperingv end of the needle valve 18 and out through the ducts 23 into the mixing chamber 24; the air current, drawn through the air inlet 25 by the suction of the enginepassing through the orifices 52 in the sides of the tubular member 50 and up through the air inlet into the mixing chamber 24a past the ends of the radial ducts 23 in the valve'22.

The air 'passage 25 completely surrounds' the upper end ofthe tubular member 50 so that air enters through the evenly spaced orifices therein from all sides. The heated fuel is thus thoroughly mingled with air and passes on to the engine. j v

The construction thus far described bears a general similarity to the construction shown in United States. Patent No. 1,257,888 issued tothe applicant but is new in certain details that are hereinafter claimed.

The hotl gases used for heating the film lj `of heavy oil or other fuel in the chamber 7 and in the lchamber 12, 15, which, is surrounded by the chamber 9a, are intended to vbe extracted from the burned gases .ex-

tained in the reservoir 29. The member con- -taining the chambers 29 and 34 may be formed, preferably, integral with the walls of the chamber 1.- Y

Passing transversely through the air conduit orxpassage 25, hitherto referred to, and which extends laterally from-fthe upper member of the casing, isa slidable tube 35,

held, normally, yieldingly upward by the 35 is not vimmersed in the fuelin the tubular chamber '34. v A choke valve 37 inthe air conduit or passage 25 is mounted on a shaft 41 land carries an arm 38 which bears upon a collar 39 on the .tube 35 so that as the choke valve 37 is closing it depresses the tube V3 5 until the lower end. of said tube is immersed in the lighter oil orfuel in the tubular chamber 34. Th@ upper end of the tube 35 is sli'dablv mounted in a passage 45 in hplug 46 A whichis held in position by a l screw 47, xtending at right angles to the passage 45 is 'a passage '40 opening intothe mixing chamber or the conduit 28 adjacent its connection with the mixing chamber A24, and between the air inlet and the engine intake. The tube-35' is slidably mounted in the passage 45 in such manner, and is of such length that, when depressed by the actuation 'of the lchoke valve 37, it opens the passage 40 and'thereby establishes communication between the fuel in the tubular c hamber 34, and the passage 28 to the engine 'manifold above the-air inlet to the mixing 105 spring 36 so that the lower end of the tube mixing chamber,

*tube 35 and passage40 where it commingles with the, air passing through the mixing chamber and passage 28. The choke valve 37 is adapted to be manually controlled. It is customary in the starting of 'a motor to approximately close the air intake passage for the purpose of producinga .richer mixture of air and fuel passing to the motor, and the action of closing,.or partially closing, the choke valve serves to depress thetube 35 into the lighter fuel andr to thereby pro- `vide an easily ignit-ible mixture. for starting. As the motor gains speed, the choke valve is opened, which raises the tube 35 out of the lighter oil, the motor having by this time generated sufficient heat'in the exhaust for heating the heavier fuel, and the motor from this time on is supplied with the heavier fuel previously heated.

By the described means it will be seen that the supply of the light oil at starting, the cutting off of the light oil, and the sup plying of the heavier oil, are accomplished by only the manipulation of the usual means employed for controlling the supply of air through a carbureter as ordinarly employed. Having described the invention in such ,manner as to enable those skilled in the art to which it appertains to make and use the same, what I claim is: y

1. A carbureter having a fuel reservoir,l a mixing chamber, an air inlet for the mixing chamber, a fuel port .opening into the a choke valve for controlling the quantity of air admitted to the mixing chamber, a adapted to be submerged in the fuel of the fuel reservoirand aconnection between the choke valve and said duct constructed and arranged o establish communication between the fuel in the fuel reservoir andthe mixing chamber in response to movement of the choke valve toward closing position,

4and to cut off said` communication in -response to movement of the choke valve toward open position.

2. A carbureter having a fuel reservoir, a mixing chamber, an air inlet for the mix# ing chamber, a fuel port opening into the mixing chamber, a choke valve for controlling the quantity of air jadmitted to the mixing chamber, a fuel duct having one end adapted to be submerged in the fuel of the fuel reservoir, and a connection between the choke valve and said duct constructed and arranged to submerge one'endof said duct in the fuel of the fuel reservoir in response fuel duct having one end vsage and into the fuel reservoir,

to movement of the choke valve toward closing position, and to withdraw the end of said duct from the fuel in said fuel reservoir in response to movement of the choke valve toward open position.

3. A carbureter having a fuel reservoir, a mixingchamber, an air inlet for the mixing chamber, a fuel port opening into the mixing chamber,-a choke valve for control- `ling the quantity of air admitted to thew mixing chamber, a fuel duct comprising a slidable tube open at both ends and adapted to have its lower end immersed in the fuel of the fuel reservoir and thereby establish communication between the fuel in the reservoir and the fuel port opening' into the mixing chamber, coperating means on the sliding tube and the choke valve whereby movement of the choke valve into closing position slides said tube so that its end dips into the fuel of then reservoir and establishes communication between said fuel and the mixing chamber and whereby movement of the choke valve toward open position v causes the tube to rise from the liquid and cut off such communication. l

4. A carbureter havinga fuel reservoir, a mixing chamber, and air inlet for the mixing chamber, a fuel port opening laterally into the mixing chamber, a passage intersecting said fuel port, a tube slidable in said intersecting passage and having its lower end adapted to be immersed in the fuel of the fuel reservoir, said tube having its opposite ends open, a choke valve for controlling the quantity of air admitted to the mixing chamber, and mechanical` connections between the choke.' valve and said tube .constructed and arranged so that moveyment of the choke valve toward closing po- 5. A carbureter having a mixing chamber, a fuel reservoir, anair inlet port at the lower side of said mixing chamber, an air passage extending laterally and communieating with said air inlet port, a fuelinlet passage to the mixing chamber extending laterally and discharging into the mixing chamber above the air inlet port, a passage intersecting theysaid fuel inletpassage, a fuel conducting tube slidable in said passage that intersects the laterallyextending fuel passage into the mixing chamber and is adapted to open and close it, said fuel 'conducting tube `extending transversely Y through the laterally extending air pasa choke Jvalve infthe air passage, and a connection between the choke valve and the slidable,

fuel conducting tube of such character that closin movement of the choke valve causes mixing chamber, and openlng movement of the choke vvalve causes the tube to rise out of the fuel in the fuel reservoir and close the fuel passage into the mixing chamber.

6A arbureter having a' mixing chamber and a fuel n reservoir, an air inlet port in the mixing chamber, an atomizing valve having a normal tendency to close said air inlet, said atomizing valve having a tubular stem rovided with a fuel inlet arranged to dip into the fuel in said fuel reservoir, radial passages in the 4valve adapted to discharge fuel into the air passing through said inlet port, said tubular stem having a constricted portion in its bore, a tapermg fuel metering valve enteringthe lower end of said hollow stem and cooperating with said constricted portion so as to increase or decrease the size of the fuel passa e through said stem according as the said atomizing valve ascendsor descends in response to the movements of an engine..

7. A vcarbureter having a mixing chamber provided with an air inlet port,- a tubular member coaxial with the inlet'port, said tubular member having lateral ports equally spaced below said inlet port, an air conduit surrounding said tubular member and ports and communicating with an air passage extending laterally from the chamber, an atomizing valve having a tendencyto close said inlet port, said valve having a hollow of saidv hot gas chamber, and means whereby heatedfuel vin the central, exterior cham# ber,V may be drawn into the mixing chamber.

9. A carbureter having a mixing chamber provided-with an air inlet port', a main fuel reservoir, and a central chambered member depending beneath the fuel reservoir, passages adapted to conduct the fuel "from the main reservoir tothe said chamberedvmember, an atomizing valve adapted yto control stem adapted to receive fuel, and radial passages extending from the bore of said stem to the edge of the valve.

8. Acarbureter having a mixing chamber and a main fuel reservoir provided with a rentrtant frusto-conical bottom, a central chambered; member depending below said conical -bottom and partially surrounded by it, a thin heat conducting wall spaced from 'the lower side of said frusto-conical bottom and so arranged as to confine a film of fluid fuel, means to .admit fuel from the main reservoir into the ilm A,confining space, means to admit fuel from thefilm confining space into the central chambered member, a hot gas chamber surroundin the central chambered member, the thin lieat conducti ingwall constituting a portion of the wall 'said atomizing valve having a central ho the air inlet port to they mixing' chambel,

low stem provided with a piston "a't its lowev endv adapted to t said central' depending.

`chamber,'said piston having a passage'fto permit fluid t'o pass from one side of itto means forconducting fuel from one of said reservoirs yintovthe mixing chamber and atomizing it, means for heating said fuel by hot gases during its passage into the said fuel conducting means, a fuel duct leading from another fuel reservoir to the mixing chamber .above the air inlet port, a choke valve inthe lateral air passage, and connections between the choke valve and fuel duct responsive to the closing movement of the choke valve to effect communication between the fuel and the mixing chamber, and responsive to an opening movement of said valve to cut off communication between said fuel and mixin chamber.

11. A carbureter comprising a casing hav- .ing 'a mixing chamber and separate fuel resnections-between the choke valve and fuel 'the other andsaid stem having a fuel inlet duct responsive to the closing movement of the choke valve to effect communication between the fuel and the mixing chamber, and responsive to an opening movement of said v valve to cut off communication between said fuel and mixing chamber. y

In testimony whereof Iaix my signature.

ELDEN r. LAMB. 

